Evaluation of Sympathetic Activity Effects by the BackBeat Medical Cardiac Neuromodulation Therapy (CNT).

Inclusion Criteria: * Subject is already implanted with a Moderato IPG that can be used to deliver CNT pacing signals, whether CNT pacing was activated or not. * Subject is willing and able to comply with the study and procedures. Exclusion Criteria: * Subject is dependent on 100% ventricular pacing. * Subject has symptoms of heart failure, NYHA Class III or greater. * Subject has an ejection fraction of 25% or less * Subject's systolic blood pressure is less than 100 mm Hg on the day of recording. * Subject has decompensated heart failure * Subject has significant (\>3+) mitral regurgitation, aortic regurgitation, or aortic stenosis * Subject has permanent atrial fibrillation. * Subject has Atrial fibrillation on the day of the study. * Subject has hypertrophic cardiomyopathy, restrictive cardiomyopathy, or interventricular septal thickness ≥15 mm. * Subject is on dialysis * Subject has prior neurological events (stroke or TIA) within the past year or a neurological event (stroke) at any prior time that has resulted in residual neurologic deficit. * Subject has a history of autonomic dysfunction. * Women who are pregnant or breast-feeding. * Subject cannot or is unwilling to provide informed consent